I would be wary of waxed cotton. As it is a good water repellant product it has issues with protecting you at warmer tempertures and the lifespan of the wax coating is not very long. Waxed cotton also becomes somewhat rigid at cold temperatures. The best fabric that is similar to waxed cotton is oilcloth. It doesn't become nearly as rigid when cold and the waterproof treatment lasts significantly longer. I would still suggest looking at DryAngler
where they sell Drift Creek Outdoors. I've been nothing but impressed with their jackets.